The Complete Guide to Landscape Design, Renovation, and Maintenance
by Cass Turnbull

ALL ABOUT HOW TO PRUNE HEDGES
Hedges can be grown in two styles, the formal and the informal. Formal means that you shear them, informal means that they look more natural and you selectively prune them to control size and maintain their good looks.

A big difference between formal and informal hedges is the amount of time it takes to maintain them. Formal hedges have to be sheared all over to keep them looking tidy, which may be fast, but must be done frequently. To control size you cannot miss a year. Informal hedges can be selectively pruned, and therefore generally need only touch-ups of unruly branches. They are easier to reduce in size and look better when reduced this way. Both styles of hedges have the purpose of providing a natural screen or wall. A formal hedge (in addition to performing a function) is a style which is good as a contrast to other plants. Contrast is one of the major elements of an esthetically pleasing yard. So that, whereas an entirely sheared yard may look dumb and dull to some people, a perfectly straight sheared hedge behind your perennial flower bed constitutes valuable contrast in your yard and is very tasteful.

To prevent leggy hedges, shear top slightly narrower than the bottom.

Avoid Leggy Hedges
Avoid creating a hedge with legs. It is considered uncouth to have such a hedge. You want a hedge that is dressed to the ground, as in totally formal. Hedges get leggy when sun cannot reach down low, so that lower leaves are shaded out. The way to prevent this is to shear your hedge into a slightly pyramidal fashion so that the top does not shade the bottom. By fall, the top will have grown back more vigorously than the bottom and it will look more nearly square. In the colder part of the United States, the pyramidal form helps prevent damage to the top from heavy snowfall as well.

Common mistakes are following the ground level and lowering the hedge as your arms get tired.

Other errors: two people doing the job; trying to follow a string tied to the chain link fence.

Creating a Nice Hedge
The major criteria for nice hedges are levelness and straightness. This is a lot harder to achieve than one might suppose. As people who have sided a house or laid bathroom tile know, the work may look even close up, but when you stand back, OOPS!

Mistakes to avoid are (1) following the ground level, (2) lowering the hedge top as your arms get tired, (3) following last year's mistakes, cutting just above the old cut, (4) having two people do it, and (5) following a string tied between two posts or tied along the adjacent chain link fence.

Some people try using a carpenter's level on a board, or they rig up a one-dimensional hedge template and move it along. Some pick a part of their body to cut to. Once Norman the Foreman at the Parks Department where I worked told the crew to cut at knee level, which, of course, varied according to whose knees you were talking about. We sang it to the tune of "She's got Bette Davis Knees."

For very tall and very long hedges, rent scaffolding to help you cut the hedge perfectly level. The best method I've found for general hedge cutting is the haircut method: Take a little off at a time and constantly, frequently stand back and walk around, looking at your hedge from different angles. Get it right the first time using loppers--then follow your old cuts the next year using shears or hand pruners.

For very tall, very wide hedges, create a "false front," then shear the top from inside.

Hedge Width
A hedge needn't, shouldn't, be wider than one person can reach across on a ladder. If your hedge has gotten very broad, consider serious reduction. When you drastically reduce the height, or more likely the width, of your hedge, you will want to do it in the early spring so that it will most quickly and vigorously hide those ugly bare branches. Be sure your hedge is the type that will green back up if pruned hard; many needled evergreens won't. If you are a lazy gardener and want to shear only once a year, try a tidy cut in June or July, when it is least likely to promote new shaggy growth. If you have a truly giant laurel or boxwood hedge with only one side facing the public, you may want to turn it into a false front by taking out the unseen inside, or make it into a horseshoe by chainsawing out the inside. This will make it possible for you to set up your ladder inside or behind and shear the top.

Have you ever wondered about those giant sheared things on English estates? How do they do that? That giant holly gum drop? That two-story yew that looks like elf hat? Well, first off, these plants have been sheared from the time they were little, every year, so that they are incredibly bushy and dense right through to the very inside, and the gardener actually stands or ties the ladder onto the shrub itself. The plants chosen are slow growing and only need to be done once a year, usually. Generally the leaves are small.

Hedge Size
Which brings us to the point of your laurel or photinia hedge. You (or someone else) planted laurel or photinia because you wanted a wall fast. Since these bushes really want to be trees, they oblige you by growing fast. But they don't stop when they get to the size you want, they keep growing--fast. They are prone to developing legs and their big leaves don't look as nice sheared as do fine-leaved plants. That's what you get for being so impatient.

You will probably want to shear laurel and photinia more than once a year to keep them looking nice, and after you shear them, go back and go over everything with your hand pruners and selectively prune out the ugly stubs and exposed branches. If either of these have been let go so that you've had to place a twelve-year-old on a plywood board on top of the hedge to shear the eight-foot expanse on top, you may rest easier knowing that these incredibly tough plants can be pruned back hard, which is gardenese for cut way, way back, to a couple of feet off the ground if you like.

Do not, however, try this radical reduction with your needled evergreen. It won't work. Most of the conifers and needled evergreens, except yews, develop the dead zone of bare wood on the inside of a sheared plant. It gets bigger every year. If you shear deeply into it, it will not green up again. So, generally speaking, every year your needled evergreen hedge must get incrementally larger. The qualities that make good shear material are small leaves, spaced closely together, slow growing and tough enough to take it.

Deciduous Hedges
Some people plant deciduous shrubs for hedges--privet, hornbeams, and the like. They often need more severe early training than conifers in order to build a dense bushy framework, especially around the base. It is even possible to use blooming things like forsythia, escallonia, quince and camellia. I wouldn't, but I'm prejudiced. Pyracantha is often used as hedge material and is also valued for its decorative berries. Your timing may vary in order to retain as much "show" on these berried and flowering plants as you can. Do not top your conifer hedge until it reaches the height you wish it to be. Shear deciduous material all over repeatedly as it grows to its desired height.

Avoid cutting into the dead zone on needled evergreens. If cut deeply, they will not "green back up."

Power Trimming
If you have inherited a home with a veritable fortress of hedging around the perimeter and you want to keep it (I'd take it out and plant a perimeter of tasteful groupings of shrubs), you may choose to invest in a pair of electric or gas powered hedge trimmers. The two most hated pieces of power equipment in the Parks Department were chainsaws and power hedge shears. That's because they rarely made it through a group project alive. I always loaded up as many as I could lay my hands on, so that when one died, I could switch to a new one. It reminded me of a pony express rider changing to a fresh horse. I also brought two extra chains for the chainsaw and some WD-40___ for the blades of the power hedge shears, to use when they got sticky and wouldn't move.

It's a wise idea to sharpen both of these pieces of equipment before, during, and after a big job. This is because the amount of physical effort required increases exponentially with the dullness of the blade. Also you can get into serious accidents with both these power tools, the chances of which also increase as you get tired from forcing dull blades through your shrubbery. People are very reluctant to stop to rest once they start this equipment, especially when it's taken thirty-five pulls to get it started, thus ensuring operator exhaustion from the beginning. Tired people with dull chainsaws cut their foreheads open (tip kickback); tired hedgers tend to saw into their thighs. These tools are, on the other hand, useful time and labor saving devices, if you use the best and the sharpest and take the time to rest and resharpen. I use my local saw sharpener a lot, and I keep extra chains on hand. I sharpen things after I'm done, so that my chainsaw or trimmer is ready when I go to use it six months later. Electric saws and shears tend to start more easily than gas powered ones and are much lighter in weight, so you don't get as tired. Also, you don't get gassed to death by the exhaust fumes. Be careful with your cord in the rain, however, and don't cut it and electrocute yourself.

People just don't realize the danger, drama, and high excitement that waits for them in their own back yards. Now that you know all about hedges, you are ready for the assault. Let's be careful out there!

GOOD TO SHEAR
Yew Japanese Holly
Boxwood Box Honeysuckle
Privet Pyracantha

OPTIONAL TO SHEAR (Some would argue)
English Laurel Quince
Some Junipers Osmanthus
Hemlocks Evergreen Euonymus
Aborvitae Oregon Grape
Holly Photinia
Abelia Escallonia
Bamboo Cotoneaster

DO NOT SHEAR
Deciduous Flowering Shrubs Lilacs
(Forsythia, Deutzia, Roses
Kolkwitzia, Philadelphus, Viburnums
Weigela) Rose of Sharon
Rhododendrons Pieris/Andromeda
Most Barberries Kalmia
Spireas Deciduous Euonymous
Aucuba Camellias

CRIMINAL TO SHEAR
Laceleaf Maples Magnolias
Deciduous Azaleas Witch Hazel
Harry Lauder's Walking Stick Dogwoods
Contorted or weeping things Doublefile Viburnums

SUMMARY
- Good plants for shearing have small leaves spaced closely together. They are slow growing and tough. They will not become diseased or die back as a result of repeated shearing.
- Formal sheared hedges should be level and thin enough for one person to reach across.
- Make the top of a hedge narrower than the bottom.
- Needled evergreens (hemlock, pyramidalis, etc.) cannot be radically reduced in width. They will not readily break bud and green back up, as will most broadleaf plants.

Forward to Shear Madness

Back to Pruning Tree-Likes